search for: i8086

On Fri, Aug 01, 2014 at 07:43:08AM -0700, Zetan Drableg wrote: > Ok now we are getting somewhere! Those old vars did the trick. > libguestfs-test-tool launched with qemu-wrapper as expected with the > debug port open. > Now on to the fun part! > > (gdb) set architecture i8086 > The target architecture is assumed to be i8086 > (gdb) break *0x7c00 > Breakpoint 1 at 0x7c00 > (gdb) target remote :1234 > Remote debugging using :1234 > 0x0000fff0 in ?? () > (gdb) cont > Continuing. > > The breakpoint you documented as when the boot sector has be...

Hi! It's indeed better to open a new thread for this. So, here's my test session: $ qemu -fda extlinux.144 -s -S Then in another terminal: $ gdb extlinux.elf (gdb) set architecture i8086 (gdb) target remote localhost:1234 Remote debugging using localhost:1234 0x0000fff0 in ?? () at localboot.inc:68 68 jmp kaboom ; If we returned, oh boy... How does "jmp kaboom" get here? We are at the BIOS entry point: (gdb) display/10i $cs*16+$eip 1: x/10i $cs * 16 + $eip 0xffff0...

On Thu, Jul 31, 2014 at 03:32:18PM -0700, Zetan Drableg wrote: > Ok - > By the way, I looked into updating out KVM versions. Since we already > have so many KVM servers of this version in production, I can't easily > forklift update everything without much testing. > > exec /usr/libexec/qemu-kvm -s -S "$@" > > export LIBGUESTFS_HV=/root/work/qemu-wrapper

...info. > repo > [ol6_debuginfo] > name=Oracle Linux 6 debuginfo > baseurl=http://oss.oracle.com/ol6/debuginfo > gpgkey=https://oss.oracle.com/ol6/RPM-GPG-KEY-oracle > gpgcheck=1 > enabled=1 > > yum update > yum install kernel-debuginfo > > (gdb) set architecture i8086 > The target architecture is assumed to be i8086 > (gdb) symbol-file /usr/lib/debug/lib/modules/2.6.32-431.20.3.el6.x86_64/vmlinux > Reading symbols from > /usr/lib/debug/lib/modules/2.6.32-431.20.3.el6.x86_64/vmlinux...done. > (gdb) target remote :1234 > Remote debugging using :1...

Hi, Martin Str|mberg wrote: > And given that space in isohdpfx is very limited (432 bytes) perhaps > the right thing might be to not have that xor in there. > But then better safe than sorry, and given that there is space _now_, > why not? I still agree. But while answering Ady's questions i get to a question of my own: Do all six fixed isohdp*.bin variations still fit into 432

...Then you can look at the resulting .lst files to see what values the instructions turned into (except for values that are determined at link time). Also you should immediately see the offset that you want to patch instead of needing to search. Another good command is "objdump -D -b binary -m i8086 -M data16,addr16 isohdpfx.bin" if you want to see the assembly code of something compiled for barebones 16-bit x86. -- MartinS

Hello, I create simple script based on virt-resize as example, and I want to copy freebsd installation between vm's http://pastebin.com/ZK7Bg6FQ At boot I receive error "Missing operating system". There is first 1M of images: http://i.libc6.org/media/opensource/template.img http://i.libc6.org/media/opensource/cloned.img Images is similar except partition table on 0x1BE address It

...SUPPORT to 1 and #includes isohdpfx.S. > - I am quite clueless what the code between "1:" in line 130 and "next:" > in line 150 does. That piece is to move the running code from (0x0000:)0x7x00 to somewhere else. The comment says 0x600 and "objdump -D -b binary -m i8086 -M data16,addr16 bios/mbr/isohdpfx.bin" confirms this. This is done so the next bootloader can be loaded at 0x7x00, which is a requirement and/or expected by any bootloader. > - Then it tries whether INT 13 AH 41H is supported and if so, patches > itself to use INT 13 AH 42H for rea...

...thing else, but I guess the big lines are the same. - Add "-ggdb3 -O0" to GCCWARN in mk/devel.mk. - I use the following commands in my .gdbinit to load the symbols of the main file and set the right architecture. file bios/core/lpxelinux.elf target remote localhost:1234 #set architecture i8086 set architecture i386 set osabi none Depending whether you're debugging 16 bits or 32 bits code, you will need to set the architecture accordingly. You can switch on the fly if the disass command decode the instructions incorrectly. (At least or worked for me, I use a 32 bits OS.) Note that th...

On Wed, Jan 13, 2016 at 01:22:17AM +0100, Celelibi wrote: > 2016-01-12 22:21 UTC+01:00, Tal Lubko: > > On Mon, Jan 11, 2016 at 07:20:20PM -0500, Shao Miller wrote: > >> > >> Yes, you can print debug-output from custom builds. > >> > > > > Regarding my other question (debugging). > > I know it is possible to use prints for debugging. > > I

I got a qemu crash and errors reported in bochs while trying to get latest core32 branch working (pxelinux): qemu: fatal: Trying to execute code outside RAM or ROM at 0xe6e8aa07 EAX=6e0c7811 EBX=000034b3 ECX=ca68b338 EDX=00000048 ESI=750e3fff EDI=00000020 EBP=d07e4988 ESP=00102324 EIP=e6e8aa07 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES =0028 00000000 ffffffff 00cf9300 CS =0020